As part of a drive to push green innovation in the racing world, the American Le Mans series has announced the Green Challenge. Basically, the Environmental Protection Agency and the Department of Energy are partnering with SAE to encourage race teams to use renewable fuels, alternative engine configurations, regenerative braking and emissions controls. Chevy unveiled this Corvette race car, plastered in E85 stickers, to highlight the announcement. We're bigger fans of the Vantage GT2, which is also powered by ethanol, or the Lexus IS350 GT2.

No emissions targets or environmental impact limits have been set. While we would love to see racing reduce its impact on the world around us, thus furthering research into enabling passenger cars to do the same, we can't help but feel efforts like this merely pay lip service to being environmentally friendly in order to placate critics.